1. Field of the Invention
This invention relates generally to a dental treatment chair system and more particularly to a dental treatment chair system which makes it possible to suitably change the direction in which to manipulated a dental instrument in accordance with the position and type of treatment a patient undergoes and with the position and posture the operator takes during a particular treatment.
2. Prior Art
In dental treatment, it is considered essential for optimum treatment, to change the direction in which an operator manipulates an instrument in accordance with the purpose of treatment, the oral region being treated and the position and posture of the operator. Accordingly, there have been many ideas as to where the instruments should be disposed with reference to a treatment device. A description will now be given roughly outlining the problems in conventional devices of this nature, which have not yet been solved.
In similar types of conventional devices, Type (a) features instruments which are directly mounted to a backrest freely tiltable with respect to the seat of a treatment chair; Type (b) features instruments which are mounted to a tray table or tray arm; Type (b-2) features instruments which are mounted to a spittoon portion and Type (b-3) features instruments which are mounted to a movable cart, etc. The types of conventional devices described above have both pros and cons. In particular, Type (a), in which the instruments are directly mounted to the backrest, is much more functional. Type (a) is more functional because it enables the assembly of flexible connection pipes connected to the instruments, stores the pipes inside the backrest with the pipes out of view and dispenses with a long arm and an exposed support which are provided independently of the chair device, saving such sagging exposure of the flexible connection pipe being provided with a tray and a spittoon and further increases manipulability of the instruments without forced posture on the part of the operator, enhances the outer apperance of the invention and does not cause the patient to feel wariness or terror. The present invention is an improvement over Type (a) and a description will now be given of the present invention with reference to the prior art of Type (a) and also in conjunction with its inherent problems, which have not yet been solved.
The device of Type (a) (of the Prior Art) is designed so that the instruments are detachably mounted either to the shoulder of a backrest, to the side of a headrest or to both the shoulder and side (Japanese Pat. No. 444,604, equivalent of U.S. Pat. No. 3,198,574). The device of Type (a) is advantageous in that the operator is seated during treatment of a patient and is relieved of the trouble and effort of pushing himself onward or twisting himself to reach an instrument irrespective of whether the instruments are mounted on the right or left side of the treatment chair, thus making treatment more efficient and lessening the fatigue on the operator. But this design is still problematic in that during the treatment activity in a seated position of 9 to 12 o'clock the flexible connection pipe entwines around the operator's hand and obstructs his field of vision thereby interfering with the treatment activity, as will become apparent from a description to be given presently.